This invention relates to an illuminated button and more particularly to a multiple color illuminated button.
Buttons and knobs are used in many different applications as a means to control a device or functions of a device. For example, an automobile will have push buttons to activate the heating, ventilation or air conditioning functions. Similarly, the radio in an automobile will have push buttons or knobs to control the volume, adjust the receiver frequency, activate receiver presets or cassette tape functions.
Furthermore, these buttons are often used in a low light environment such as an automobile at night. Thus, it is necessary to illuminate the buttons so that the user can easily locate the button to activate the device or function. Often, these buttons are illuminated by a light source which is located behind the button. The light is then transmitted through a portion of the button so that the user can easily locate the button in a low light environment.
In order for the user to identify the function of the button, the surface of the button contains letters or graphics or both which describe the function of the button. For example, the button may have the letters "R DEF" which is the abbreviation for rear window defroster and may also have a graphic which shows heat rays directed at a rectangle which represents a window.
Sometimes, the users of these buttons require that the letters or graphics should have a first color during the day time, i.e. a reflected color, and a second color during the night time, i.e. a transmitted color, when the button is illuminated from behind. Thus, these buttons have one color day time and a second color night time.
A desirable feature or characteristic for these buttons would be the use of multiple colors for the letters and graphics. Specifically, there is a need for a button which has two colors for the letters and graphics during the day time and two colors for the letters and graphics during night time. For example, during the day time the letters would be a first color and the graphics would be a second color. During the night time when the button is illuminated by a light source located behind the button, the letters would be a third color and the graphics would remain the second color. Consequently, there is a need for a two color day time and two color night time button.
Another desirable feature or characteristic for these buttons would be a manufacturing method which reduced manufacturing costs, improved quality and permitted greater flexibility in the manufacturing process. The previous method of manufacture utilized a single component construction with several coats of paint.
This previous method of manufacture created several problems. For example, when several layers of paint are used to manufacture a button, solvents are trapped between each layer of paint even if the catalyst paints are fully cured. When the buttons are assembled into the device, i.e., radio or dashboard assembly, and are used in environmental extremes of hot or cold, the heat will soften the residual solvents and the paint on the buttons will become tacky or viscous. The buttons will then bind or stick in the device which is not desirable.
The trapped or residual solvents also present a further problem. The multiple layers of paint trap the solvents beneath the top or upper layer of paint, which is superficially cured, and prevents the solvents from escaping or evaporating through the top layer of paint. Consequently, the initial bond between the molded substrate and the first layer of paint is undermined by the pressure of the solvents attempting to escape from beneath the top layer of paint. Thus, the paint layers delaminate from the molded substrate which is not desirable.
Another problem with painting the buttons is the difficulty in the controllability and repeatability of the painting process. The users of these buttons specify tolerances with respect to transmitted color values. The thickness of the paint layer which is applied to the button has a direct relationship to the transmitted color value of the graphics or letters. The thickness of the paint layer will vary when a spray painting process is used to apply the paint layers. In addition, the paint color will vary between different paint lots during the production process.
Another problem encountered in the manufacture of the buttons is the difficulty in applying paint or other decoration to any surface other than the top of the button due to the size and depth of the button. Specifically, it is very difficult to apply paint or other decoration to the inside of the button. Consequently, there is a need for a manufacturing process which facilitates the application of paint or other decoration to the button.
Accordingly, it is an object of this invention to provide an illuminated multiple color button which has two reflected colors during the day time and two illuminated colors during the night time.
Another object of this invention is to provide a manufacturing method for illuminated multiple color buttons which reduces manufacturing costs, improves the quality of the product, and permits greater flexibility in the manufacturing process.
An additional object of this invention is to provide an illuminated multiple color button which has a minimum number of paint layers.
A further object of this invention is to provide an illuminated multiple color button which will not be affected by environmental extremes, such as heat.
Another object of this invention is to provide an illuminated multiple button whereby the paint layers will not delaminate from the molded substrate.
An additional object of this invention to provide a manufacturing method for illuminated multiple color buttons which has a controllable and repeatable method of applying the paint layers to the button.
A further object of this invention is to provide a manufacturing method for illuminated multiple color buttons which facilitates the application of paint or other decoration to the button.
Other objects and advantages of the invention will become apparent upon reading the following detailed description and appended claims, and upon reference to the accompanying drawings.